<!DOCTYPE html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/resources/testdriver.js"></script>
<script src="/resources/testdriver-vendor.js"></script>
<script src="../resources/orientation-event-helpers.js"></script>
<script>
'use strict';

sensor_test(async (t, sensorProvider) => {
  const motionData = generateMotionData(1.1, 2.1, 3.1,
                                        1.2, 2.2, 3.2,
                                        1.3, 2.3, 3.3);

  let firstListener = null;
  let secondListener = null;
  let firstEventCount = 0;
  let firstPromise = new Promise(resolve => {
    firstListener = (event) => {
      assert_true(event instanceof DeviceMotionEvent, 'event is DeviceMotionEvent');
      assert_equals(event.type, 'devicemotion', 'event.type is devicemotion');
      assert_true(event.target instanceof Window, 'event is fired on the window object');
      assertEventEquals(event, getExpectedMotionEvent(motionData));
      window.removeEventListener('devicemotion', firstListener);
      if (++firstEventCount == 1) {
        window.addEventListener('devicemotion', secondListener);
      }
      resolve(event);
    };
  });

  let secondEventCount = 0;
  let secondPromise = new Promise(resolve => {
    secondListener = (event) => {
      assertEventEquals(event, getExpectedMotionEvent(motionData));
      window.removeEventListener('devicemotion', secondListener);
      ++secondEventCount;
      resolve(event);
    };
  });

  setMockMotionData(sensorProvider, motionData);
  window.addEventListener('devicemotion', firstListener);
  await firstPromise;
  await secondPromise;
  assert_equals(firstEventCount, 1, "Too many events fired for the first listener");
  assert_equals(secondEventCount, 1, "Too many events fired for the second listener");
}, 'Tests that adding a new devicemotion event listener from a callback works as expected.');
</script>
